#include <sys/types.h> 
#include <sys/socket.h>  
#include <stdio.h>  
#include <netinet/in.h>
#include <arpa/inet.h>  
#include <unistd.h>  
int main() {
	int server_sockfd, client_sockfd;  
	int server_len, client_len;
	struct sockaddr_in server_address;  
	struct sockaddr_in client_address;  
	char ch = '2';

	server_sockfd = socket(AF_INET, SOCK_STREAM, 0); 
        server_address.sin_family = AF_INET;
	server_address.sin_addr.s_addr = inet_addr("192.168.232.128");
	server_address.sin_port = 9734;
	server_len = sizeof(server_address);
	bind(server_sockfd, (struct sockaddr*)&server_address, server_len);  
	listen(server_sockfd, 5);
	while (1)
	{
		printf("server waiting ch = %c\n", ch);  
		client_len = sizeof(client_address);
		client_sockfd = accept(server_sockfd, (struct sockaddr*)&client_address, &client_len);
		read(client_sockfd, &ch, 1);
		printf("char from client = % c\n", ch);
		ch++;
		write(client_sockfd, &ch, 1);  printf("char after write = %c\n", ch);  
		close(client_sockfd);
	}
}
